SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1101be0f85becc93d0cb82d254184228fbfda6d11e541352604f383bc012e87c' 
  AND token = 'iNYSCyd5izlhozStl/z+L6qgQHU0hZI6KCJP/o72Zsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}